The objectives are, first, to characterize the sperm enzyme phosphoglycerate kinase B (PGK-B) immunogenetically and immunochemically and, second, to determine its role in the process of reproduction. We are preparing antisera against PGK-B and its somatic counterpart, PGK-A, for use as reagents. Immunocytological techniques will be used to determine the cellular locations of the PGK isozymes in testes and to test for the presence of PGK-B in oocytes and blastocysts. The phylogenetic relationship of the two PGK isozymes between and within species will be studied immunochemically. The effects of active and passive immunization against PGK-B on fertility and embryo survival will be studied in laboratory and farm animals.